Electric fire-alarm.



PATENTED OCT. 22. 1907.

J. A OBBSTER. ELECTRIC FIRE ALARM.

AVPPLIUATION FILED APR.25, 1907.

wmvs'slsss ATTORNEYS mitten snares JOHN A. OBESTER, 'o'r PASSAIC, new mnssr.

ELECTRIC FIRE-ALARM.

No. seams.

Specification of Letters Patent.

Patented. Oct. 22, 1907.

Application filed April 25,1907. Serial No- 370,181.

To all whom it may concern:

Be it known that I, Join A. Onns'rua, a citizen of the United States, residing in Passaic, Pass-tic county, New Jersey, have invented certain new and usciul l1n-' provements in Electric Fire-Alarms: and 1 do hereby declare the following to beat full, clear, and exact dcscription of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of reference marked thereon, which form a part of this specification.

My invention relates to apparatus for detecting the location oi fire in buildings, and it has for its-object to provide an apparatus of this nature which shall be simple in construction, positive and certain in opcration, and proof against being interfered with by dirl, dust, etc., which might, in some cases, as in mills. f actorics, etc., prevent the perfect establishment of the electrical connections uponthc apparatus being set in operation by the outbreak of lire.

' My invention will be found fully illustrated in the accompanying drawing where it appears in semi-diagrammatic form..

In the drawing, a is the main line or circuit and b its generator.

C is a bell alarm included in the circuit and (i may be another alarin of the annunciator type, the same comprising a case 6 having the orilioef, a drop 9 moving in guides in and adapted to present an index at the orilice f when it falls and rests with its lug i on the lower guide h, j a lever fulcrumed at 7c and normally resting on a stop I, in which position it is engaged by the lug i oi the drop 9 and so sustains the same, and m an electromagnet which has the lever j for its armature and is ipcludcd in the circuit a. When the circuit a is closed, alarm r: is sounded and the magnet m attracts lever l tdpcrmit the drop g to fall, as will be manifest. The alarm or alarms are located in some portion oi the building, where some one is constantly present. g

in some suitable part of the building is placed the thcrmo-actuative device shown at the extreme lolt oi the drawing. This, in the adaptation shown, is a sealed glass tube n containing mercury or other thcrmoexpansive liquid 0 and haxing a gage p, so that it is in all essentials an ordinary thermometer. -Into the bulb qat'tli e ldwr end of the tube it extends one end of the -vice is located. When the temperature in that apart ment reaches that degree, as by the outbreak of tire, the consequent expansion of the liquid in the tube until it raises high enough to contact with the end of the wire extending into the upper end of the tube, cause the circuit to be closed and set off the alarms.

Inrhe main circuit a is placed in a suitable case 1- an elcctro-magnet s which becomes energized as soon as the circuit is closed. This magnet has the armature t which is fulcrumed at 11 and normally rests on a stop '0.

In this position the armature has its free end overlapped by the end of the pawl 21. pivoted at .r and engaging in a notch y in the side of a plunger 2, holding 4 the plunger elevated. Said plunger is guided by an insulating bushing l in a metallic thimble 2 which is secured to a wall oi the case 1' by the screw 3, being in sulated' from said wall by the insulation 4. At its upper end the plunger is guided in the insulating busliing 5, said plunger being pressed towards the thimble 2 by a spiral spring (5 coiled about the plunger-between bushing 5 and a shoulder 7 on the plunger.

The wires oi the branch are indicated at 8 and 9. the former extending from the main line a to the upper end of the plunger. where it is secured byathumb screw 10,

and the latter to the screw 3 to which it is secured by a nut 11. Thus assumidg that the main circuit has been automatically closed in the manner above indicated, the magnet s is immediately energized and said magnet actuates its armature and this in turn moves pawl to so that the latter releases the plunger. hich in conjunction with the annuuciator, or alone, to on able the -lire to be more definitely located.

I do not wish to be'limited to any of the details of construction herein set forth, what 1 claim being:

The combination, with the main circuit having a normal break therein and an alarm located in said main circuit, or". a llwlllHHltfllliltiVQ circuit closer adapted to bridge said break. a branch also having a break therein comprising a metallic thimble, u circuit-closer adopted to bridge the break in the branch and comprising a rectilinear-1y movable plunger normally movable toward and into said thimble in contact therewith, a pawl normally restraining said plunger from closing the break in the branch, an

electro-magnet located in the main circuit, and an armu- 

